Trade in Works Of Art, Collectors Pieces And Antiques - Bulgaria. This data employs the subheadings of the original Harmonized System (HS1992). The United Nations Commodity Trade Statistics Database (UN Comtrade) provides a considerable amount of data on trade from over 140 countries starting in 1962. For more info, please see http://comtrade.un.org/db/mr/rfGlossaryList.aspx